1. Field of the Invention
This invention relates generally to a method for improving conventional hearing aids and, more particularly, to a method for maintaining directional hearing of an individual wearing hearing aids, either behind the ear or in the ear.
2. Description of the Background
A hearing aid is generally a simple device consisting of a microphone, an amplifier, and an output transducer. Hearing aids are classified either as in-the-ear (ITE), in which the entire device resides in the wearer's ear, or behind-the-ear (BTE), in which the amplifier, microphone, and battery are arranged behind the ear with the output transducer being generally at the ear opening. It is known to provide for some shaping of the gain or amplifier response depending upon the specific hearing deficiencies of the wearer by emphasizing higher or lower frequencies and altering the gain as appropriate. One major complaint of hearing aid wearers is that it is difficult to enjoy the benefit of the hearing aid in a noisy environment because the noise is amplified by the same amount as the signals of interest, which might be speech or music. Using filters to filter out the signals of interest from the noise has proven to be a less than satisfactory solution, because for one reason the frequencies of the signals of interest often overlap the frequencies of the noise that is masking those signals.